高阶不平衡术语:有效功率密度量化了朝着或远离局部热力学平衡的演变
M Hasan Barbhuiya1, Paul A Cassak1, Subash Adhikari1
1Department of Physics and Astronomy and the Center for KINETIC Plasma Physics, West Virginia University, Morgantown, West Virginia 26506, USA.
Physical review. E
|February 17, 2024
概括
研究人员开发了一种新指标,即高阶不平衡术语 (HORNET) 的有效功率密度,以量化非平衡等离子体系统中的能量转换. 这一新指标对于理解局部热力学平衡之外的复杂等离子体动力学至关重要.
科学领域:
- 等离子体物理学的物理学
- 非平衡的热力学 热力学
- 计算天体物理学 计算天体物理学
背景情况:
- 评估流体和等离子体中的能量转换通常依赖于比较功率密度.
- 在远离局部热力学平衡 (LTE) 的系统中量化能量转换是一个重大挑战.
- 现有的方法难以捕捉非平衡等离子体系统中能量动态的全部图像.
研究的目的:
- 引入了一种新型的度量,即高阶不平衡术语 (HORNET) 的有效功率密度.
- 量化出不同于LTE的相空间密度变化速率.
- 允许与标准功率密度进行非平衡效应的定量比较.
主要方法:
- 开发了HORNET有效功率密度指标.
- 使用细胞中的粒子模拟来计算HORNET.
- 在模拟的等离子体过程中分析了HORNET的空间变化和时间演变.
主要成果:
- 在无碰撞磁化等离子体中,HORNET计算了磁性重新连接和衰变的动力流.
- 发现HORNET是内部能量变化功率密度的很大一部分 (8-35%用于重新连接,高达67%用于流).
- 证明了在这些等离子系统中,朝着LTE或远离LTE的进化具有动态意义.
结论:
- HORNET有效功率密度是分析非平衡等离子体中的能量转换的一个有价值的工具.
- 该研究强调了天体物理学和实验室等离子体中与LTE偏差的动态重要性.
- 黄蜂具有广泛的应用,用于理解各种等离子体现象,其中非平衡效应普遍存在.
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